Garden Affiliated Faculty utilize the Botanical Garden for teaching and research in topics across disciplines including: botany, evolution, climate change, cultural connections to plants, medicine, public health, and more.
Siobhan Braybrook - Molecular, Cell and Developmental Biology
Siobhan Braybrook, Ph.D. (she/hers)
Assistant Professor, Molecular, Cell and Developmental Biology
As a group, we focus a large effort on understanding how shapes are generated during plant development. This entails detailing the process of shape generation, describing the changes in cell wall mechanics and chemistry that accompany shape generation, and dissecting the underlying molecular control mechanisms for these changes. We are also interested in the relationship between cell walls and development in algae, with a major focus on brown algae. We are also actively involved in understanding how the material properties of the cell wall, a biological composite material, contribute to its ability to control plant development. In order to really understand what is happening in development, we need to get a grasp on how the cell wall behaves as a material, what components and structures contribute to which behaviours, and how these behaviours affect physical processes such as extension, new material deposition, and diffusion.
Jessica Cattelino - Anthropology, Gender Studies, American Indian Studies
Jessica Cattelino, Ph.D.
Associate Professor of Anthropology, Gender Studies and American Indian Studies
My research focuses on economy, nature, indigeneity, and settler colonialism. My book, High Stakes: Florida Seminole Gaming and Sovereignty (Duke University Press, 2008; winner of the Delmos Jones and Jagna Sharff Memorial Book Prize from the Society for the Anthropology of North America), examines the cultural, political, and economic stakes of tribal casinos for Florida Seminoles. Currently, I’m writing an ethnography about the cultural value of water in the Florida Everglades, with focus on the Seminole Big Cypress Reservation and the nearby agricultural town of Clewiston. This project tells the human story of Everglades restoration and theorizes the co-production of nature and indigeneity in settler societies like the United States. Additionally, I lead a research team at the Center for the Study of Women that is completing an ethnographic study of gender and everyday household water use in Los Angeles. The study is funded by the UCLA Grand Challenge on Sustainable Los Angeles. I write about indigeneity and money, the anthropology of the United States, and indigenous sovereignty, and I am collaborating with photographer Adam Nadel on a museum exhibition about the inextricability of people and nature in the Everglades.
My work is influenced by scholarship in American Indian Studies and Gender Studies, and I hold faculty affiliations in both programs at UCLA. My current research is funded by the National Science Foundation (Law and Social Sciences), the Wenner-Gren Foundation, and the Howard Foundation. Additionally, I am funded through participation in a National Science Foundation Long Term Ecological Network on the Florida Coastal Everglades, for which I am undertaking wildly interdisciplinary collaboration as a co-author of a paper on phosphorus and will conduct ethnographic research on the social life of a stormwater treatment area. Recently I was a Visiting Associate Professor of American Studies at Yale University.
Thomas W. Gillespie - Geography, Institute of the Environment and Sustainability
Thomas W. Gillespie, Ph.D.
Professor, Department of Geography and Institute of the Environment and Sustainability
My past research interests have focused on using geographic information systems (GIS) and remote sensing data for predicting patterns of species richness and rarity for plants and birds at a regional spatial scale.
Mishuana Goeman - Gender Studies, American Indian Studies
Dr. Mishuana Goeman (Tonawanda Band of Seneca)
Professor of Gender Studies and American Indian Studies IDP
Affiliated Faculty in Critical Race Studies, UCLA Law
Special Advisor to the Chancellor on Native American and Indigenous Affairs
Dr. Mishuana Goeman, Tonawanda Band of Seneca, is a Professor of Gender Studies and American Indian Studies, as well as an affiliated faculty of Critical Race Studies in the Law School. She is also the inaugural Special Advisor to the Chancellor on Native American and Indigenous Affairs at UCLA. She is the author of Mark My Words: Native Women Mapping Our Nations (University of Minnesota Press, 2013) and the forthcoming Settler Aesthetics and the Spectacle of Originary Moments: Terrence Malick’s the New World (University of Nebraska Press). She is a Co-PI on two community based digital projects, Mapping Indigenous L.A (2015), which gathers alternative maps of resiliency from Indigenous LA communities, and Carrying Our Ancestors Home (2019), a site concentrating on better working tribal relationships and communications as it concerns repatriation and NAGPRA. Book chapters are included in Theorizing Native Studies (Duke University Press, 2014), Sources and Methods in Indigenous Studies (Routledge 2016), Macmillan Interdisciplinary Handbooks: Gender: Sources, Perspectives, and Methodologies (2016), Critically Sovereign: Indigenous Gender, Sexuality, and Feminist Studies (Duke University Press, 2017) and a forthcoming chapter in Biopolitics – Geopolitics – Life: Settler-colonialism and Indigenous Presences (Duke University Press). She also publishes widely in peer-reviewed journals, including guest edited volumes on Native Feminisms and Indigenous Performances. In 2020-2021 she was a Distinguished Visiting Scholar with the Center for Diversity Innovation at the University of Buffalo located in her home territories.
Carrying Our Ancestors Home: http://www.coah-repat.com/
Mapping Indigenous LA (MILA): https://mila.ss.ucla.edu/
Ann Hirsch - Molecular, Cellular and Developmental Biology
Ann M. Hirsch, Ph.D.
Distinguished Professor, Molecular, Cell & Developmental Biology
We study the “hidden” half of plants; roots–and the myriad microbes of the rhizosphere that associate with the subterranean part of the plant. We look for n beneficial bacteria and study the mechanisms whereby they help plants grow, develop, fight disease, and prosper in less than favorable environments, including climate change.
Nathan Kraft - Ecology and Evolutionary Biology
Nathan Kraft, Ph.D.
Associate Professor, Ecology and Evolutionary Biology
Our research group focuses on understanding the processes that both generate and maintain diversity in the identity, characteristics and abundances of species that are found together in natural communities, with a particular focus on vascular plants. Given that community ecology is typically “messy”- that is- it often can be difficult to generalize results from one study or species to another, and that there are over 400,000 plant species on the planet, our group primarily focuses on more general answers to community ecology questions that can emerge from a focus on the functional ecology and phylogenetic context of species.
Jeff Long - Molecular, Cellular and Developmental Biology
Jeff Long, Ph.D.
Professor & Vice Chair, Molecular, Cell & Developmental Biology
The Long laboratory is interested in the transcriptional networks that control polarity and stem cell formation during plant embryonic development. We have focused our research on the transcriptional co-repressor TOPLESS (TPL) that is involved in almost all aspects of plant development, and use a variety of approaches including genetics, genomics, biochemistry and confocal imaging in our research. Our work on TPL has uncovered multiple transcription factors involved not just in embryogenesis, but also in polarity decisions in the leaves, patterning of floral organs, and the response to the hormone auxin. We also study the chromatin modifying enzymes that TPL uses to repress transcription, which are conserved between plants and animals.
Ananda Marin - Education
Dr. Ananda Marin
Assistant Professor, Graduate School of Education
I explore questions about the socio-cultural dimensions of learning and development in everyday and intergenerational contexts. In one line of work I examine the practices that children and families use to reason and build knowledge about the natural world. I am particularly interested in (1) how families coordinate attention and observation while participating in science activities, (2) how mobility and place structure activity and (3) cultural variability in sensemaking practices such as question-asking and explaining. I also investigate Native American participation in STEM and cultural models of self as related to senses of capability and competence. Across my scholarship, I take a participatory approach and employ a variety of research designs and methods including: community-based design research, cognitive tasks, studies of everyday practices, content analysis, discourse analysis, interaction analysis and video-ethnography. Through my work I aim to answer basic research questions about development, innovate methods, and design teaching and learning tools that contribute to the goals and well-being of Indigenous and non-dominant communities.
Luke Nikolov - Molecular, Cell and Developmental Biology
Luke Nikolov, Ph.D.
Assistant Professor, Molecular, Cell and Developmental Biology
To attract pollinating animals, plants display an elaborate array of color, form, and scent?but the ultimate reward for the pollinators is nectar, a complex sugary liquid with distinct composition across species. Nectar is produced in nectaries, secretory structures with diverse organization broadly distributed in plants. We are working to understand the developmental basis of nectary formation and nectar production. Using comparative genetics and genomic tools, the Nikolov Lab is identifying genes that control how and where the nectaries are built, and the mechanisms responsible for nectar synthesis and secretion. These findings will provide insight into a plant-animal mutualism important to agriculture and bee health, and will stimulate future applications to increase crop yield by enhancing the ecosystem services of pollinators.
Cully Nordby - Institute of the Environment and Sustainability
Cully Nordby, Ph.D.
Associate Director, UCLA Institute of the Environment and Sustainability
Dr. Cully Nordby is the Associate Director of the UCLA Institute of the Environment and Sustainability. She has devoted her career to educating and empowering students to summon the future they seek. She was instrumental in building the Institute’s academic program from one undergraduate minor to a full suite of five programs including a B.S. in environmental science, two doctoral programs and the Leadership in Sustainability graduate certificate.
Elsa Ordway - Ecology and Evolutionary Biology
Elsa Ordway, PhD
Assistant Professor, Department of Ecology and Evolutionary Biology
My research examines terrestrial social-ecological systems in the context of two globally pressing challenges: climate change and increasing demands for land to accommodate food, fuel, and fiber production for ten billion people. How we choose to address these challenges will have far-reaching impacts on ecological processes, biodiversity, and society. Combining remote sensing, field observations, models, and socioeconomic analyses, I integrate theory and methods from ecology, earth science, economics, and land system science to gain new insight into pattern and process across scales in forest ecosystems in the context of global environmental change.
Noa Pinter-Wollman - Ecology and Evolutionary Biology
Noa Pinter-Wollman, Ph.D.
Associate Professor, Ecology and Evolutionary Biology
Many biological systems are complex aggregates of multiple agents working together towards collective, higher-order goals, and evolution acts on variation in these emergent collective properties. There is no central control dictating the activities of members in the assembly. Instead, agents use local signals that determine their behavior and are received through an intricate interaction network resulting in collective phenotypes. Thus, the composition of a group and the way its members interact affects the success of the group as a whole, just as the composition of any sports team dictates its success in the league. The Pinter-Wollman lab examines the emergence of collective outcomes from group composition by combining field and lab studies with computer simulations, theoretical work, image analysis, and social network analysis. We are also interested in the interplay between conservation biology and animal behavior. Examining the behavior of animals can provide important assessment tools for conservation actions and insights on preserving biodiversity. At the same time, wildlife management actions can provide unique opportunities for studying interesting questions in animal behavior.
Debra Pires - Life Sciences
Debra (Deb) Pires, Ph.D.
Instructional Consultant and Academic Administrator – Center for Education Innovation in Life Sciences
The Center for Education Innovation & Learning in the Sciences (CEILS) creates a collaborative community of instructors committed to advancing teaching excellence, assessment, diversity, and scholarship, resulting in the enhancement of student learning experiences in the Life and Physical Sciences at UCLA.
Tara Prescott-Johnson - Writing Programs
Dr. Tara Prescott-Johnson
Continuing Lecturer in Writing Programs and Faculty in Residence
Dr. Prescott-Johnson’s research interests include twentieth-century American literature, modernism, poetry, comics and graphic novels, popular culture, and gender studies. She is the author of Poetic Salvage: Reading Mina Loy and editor of Neil Gaiman in the 21st Century. She teaches English Composition 3, English Composition 3SL (Civic Engagement), English Composition 131C: Medical Narratives, Honors 87W: The Art of Neil Gaiman, and a variety of creative Fiat Lux seminars. Dr. Prescott-Johnson enjoys bringing students to the garden to hone their observation skills, inspire their creativity, and practice writing and self-reflection.
Nathanaël (Nat) Prunet - Molecular, Cell and Developmental Biology, Microscopy Core
Nathanaël (Nat) Prunet, Ph.D.
Adjunct Assistant Professor, Molecular, Cell and Developmental Biology
Director, MCDB/BSCRC Microscopy Core
I am an Assistant Professor at the Department of Molecular, Cell and Developmental Biology (MCDB) at UCLA, where I teach Biology and Microscopy. Before opting for a career in microscopy, I trained as a plant developmental biologist, a field I chose for the wealth of imaging possibilities it offers. During my PhD and postdoc, I used a variety of widefield and confocal microscopy techniques to investigate the formation of flower buds at the tip of the stem in model plant Arabidopsis thaliana, and the genes and hormones that control this process. As a microscopist, I constantly work at the intersection of Science and Art – or SciArt – and this artistic aspect has long been an important driver for my work.
Rachel Prunier - Ecology and Evolutionary Biology
Rachel Prunier, Ph.D.
Assistant Adjunct Professor, Ecology and Evolutionary Biology
I am continuing my work understanding the genetics and evolution that underlie the diversification of plants in South Africa. This work is comprised of two main projects. One project is the assembly and annotation of the genome of Protea repens, a strangely widespread plant species from South Africa. Together with Dr. Jill Wegrzyn at UConn and Dr. Andrew Latimer at UC Davis I hope to understand the genes that have allowed it to take advantage of the challenging environment in which it lives. This project is entirely on the computer, using python and shell scripting to coordinate the complex computational challenges of assembling the genome and identifying the genes. The second project is more lab based. In collaboration with Dr. Sandy-Lynn Steenhuisen at the University of the Free State and Dr. Jeremy Midgely at the University of Cape Town in South Africa and their students, I am investigating the genetic diversity of species with different pollinators. We are also investigating the extent to which individuals in these species mate with themselves or mate with other individuals. Both of these factors: genetic diversity and inbreeding have consequences for the evolution of species.
Phil Rundel - Botanical Garden, Ecology & Evolutionary Biology
Phil Rundel, Ph.D.
Distinguished Professor Emeritus, Ecology & Evolutionary Biology
Former Director of Garden & Herbarium
Our laboratory maintains a breadth of interests centering on aspects of vascular plant adaptation to environmental water and nutrient stress. Within this context we have focused particularly on the interactions of physiological water stress and nutrient availability in limiting net primary production of arid zone plants. We are looking intensively at the relationship of seasonal changes in morphological, architectural and physiological components of plant form and function in woody desert legumes and evergreen shrubs. Our approaches in these investigations involve analysis of components of tissue water relations, photosynthetic capacity, foliar nutrient levels, leaf morphology and canopy architecture. We are very interested in applications of stable isotope ratios to ecological research studies as a means of developing integrated measurements of physiological response to environmental stress. Such measures will help us link physiological process studies to an ecosystem perspective. In addition to our work on desert ecosystems, my laboratory group maintains interests in several other areas. These include the physiological ecology of plant species in Mediterranean-type and tropical ecosystems, parallel with our desert research. We are also investigating the impact of air pollutants on photosynthetic capacity and productivity of coniferous forest trees in California.
Lawren Sack - Ecology and Evolutionary Biology, Institute of Environment and Sustainability
Lawren Sack, Ph.D.
Professor and Vice Chair, Ecology and Evolutionary Biology
Professor, Institute of the Environment and Sustainability
We study the mechanisms for function and co-existence of plant species– including responses to resources, tolerance of environmental challenges, and competition– as well as the evolution and functional consequences of diversity in plant traits. We explore processes across scales ranging from molecules to ecosystems. We have a special focus on leaf and whole plant hydraulics traits, drought tolerance, the evolution of trait diversity within lineages, and the responses of species and ecosystems to ongoing climate change. We are also very interested in applications of our research toward forest and plant species conservation under climate change.
Brad Shaffer - Ecology and Evolutionary Biology, Institute of Environment and Sustainability, La Kretz Center for California Conservation Science, Stunt Ranch Reserve
H. Bradley (Brad) Shaffer, Ph.D.
Distinguished Professor, Ecology and Evolutionary Biology
Distinguished Professor, Institute of Environment and Sustainability
Director of the La Kretz Center for California Conservation Science
Director of Stunt Ranch Reserve
Director of the California Conservation Genomics Project (CCGP)
We are a group of conservation biologists applying evolutionary and ecological theory to real world problems. Research in our lab revolves around both conceptual and organismal themes. Organismally, we tend to study amphibians and reptiles. Our fondness for these animals is one of the strongest themes in our research group, and a fundamental respect for natural history and field studies guides all of us.
We spend a lot of time developing, testing, and using genomic techniques to understand the phylogeny and population biology of species and larger lineages. Our work in the last decade has spanned phylogenetic levels ranging from the tree of life of all living turtles to detailed analyses of population history within individual species of amphibians and reptiles. In all cases, we focus on the conservation and recovery of endangered species, particularly in California. We work very closely with the La Kretz Center for California Conservation Science and the UC Natural Reserve System, and building strong collaborative research networks with local, state, and federal resource agencies is a key component of our work.
One of our recent efforts is the California Conservation Genomics Project (CCGP), a large collaborative research program that spans all 10 UC campuses, 70 principle investigators, and 230 species (so far) of terrestrial, freshwater, and marine plants and animals across California. Funded directly by the state legislature and led by UCLA, the CCGP will produce whole genome sequences of 20,000 individual organisms that together will create a map of genomic diversity and climate change resilience to help guide California conservation efforts.
David Delgado Shorter - World Arts and Cultures
David Delgado Shorter, Ph.D.
Professor, World Arts and Cultures
Director, Archive of Healing
Dr. David Delgado Shorter is Professor of World Arts and Cultures/Dance at the University of California Los Angeles. The author of an award-winning book and the recipient of the University’s top teaching award, Dr. Shorter has created three digital publications, produced and directed an ethnographic film, and curated exhibits both on-line and in Los Angeles. His research includes over two decades of collaboration with an indigenous community in Mexico and studying the borderland between the objective and intersubjective sciences. He has been interviewing psychics, mediums, and ufologists for the last decade, joining others to expand our definition of truth and knowledge.
In 2016, Shorter became the Director of the Archive of Healing, a database of medicinal folklore from around the world. The database is drawn from six university archives, over 3,200 books, and over thirty years of first hand and second hand anthropological data, spanning seven continents. Working with a team of students at UCLA studying healing across cultures, Dr. Shorter aims to develop an active archive where people and communities can benefit from the sharing of healing practices.
Dr. Shorter has been certified as having been attuned to Gokui Kaiden, the highest level of Gendai Reiki Ho, by Hiroshi Doi Sensei (Ashiya, Japan). His students include both those graduate students at the University of California, as well as those studying reiki from his private practice.
At the University, Shorter teaches Aliens, Psychics, and Ghosts; Colonialisms and Resistance; Healing/Ritual/Transformation, The Philosophy of Martin Buber; Language, Culture, and Ontology; Data Management, Research Methodologies, and Introduction to Meditation. Potential advisees and students should visit the “Academia” section of this site.
Victoria Sork - Garden Director, Ecology and Evolutionary Biology, Institute of Environment and Sustainability
Victoria Sork, Ph.D.
Director, UCLA Mildred E. Mathias Botanical Garden
Distinguished Professor, Department of Ecology and Evolutionary Biology
Distinguished Professor, Institute of the Environment and Sustainability
The evolution of local adaptation shapes the genetic and phenotypic variation that determines the survival of tree populations. A question today is how are long-lived species going to survive the human induced rapid environmental changes induced by ecosystem modification and climate change. My research team is developing the iconic California signature tree, valley oak (Quercus lobata), as a model tree system to study how trees can tolerate such rapid changes. We are also conducting a variety of ecological, genetic and genomic projects to better understand how natural selection and gene flow influence ecological and evolutionary dynamics of tree populations. Here is a list of major ongoing and recent projects in our lab.
Shannon Speed (Chickasaw) - Gender Studies and Anthropology, American Indian Studies
Shannon Speed (Chickasaw), Ph.D.
Professor, Gender Studies and Anthropology
Director, American Indian Studies Center
Past President, Native American and Indigenous Studies Association (NAISA)
Shannon Speed is a citizen of the Chickasaw Nation. She is Director of the American Indian Studies Center (AISC) and Professor of Gender Studies and Anthropology at UCLA. Dr. Speed has worked for the last two decades in Mexico and in the United States on issues of indigenous autonomy, sovereignty, gender, neoliberalism, violence, migration, social justice, and activist research. She has published numerous journal articles and book chapters in English and Spanish, as well as published six books and edited volumes, including her most recent, Incarcerated Stories: Indigenous Women Migrants in the Settler Capitalist State. Dr. Speed currently serves as the President of the Native American and Indigenous Studies Association (NAISA).
Jochen Stutz - Atmospheric and Oceanic Sciences
Jochen Stutz, Ph.D.
Professor, Atmospheric and Oceanic Sciences
Our main interest is the study of urban air pollution at night, the impact of halogen species on tropospheric ozone, and the development of new spectroscopic methods to study the earth’s atmosphere.
Wendy Giddens Teeter - Fowler Museum, American Indian Studies
Wendy Giddens Teeter, Ph.D., RPA
Curator of Archaeology, Fowler Museum at UCLA,
Lecturer, UCLA American Indian Studies
NAGPRA Coordinator, UCLA Campus
Co-PI, Carrying our Ancestors Home, https://coah-repat.com
Co-Director, Pimu Catalina Island Archaeology Project https://pimu.weebly.com
Co-PI, Mapping Indigenous Los Angeles, https://mila.ss.ucla.edu
Dr. Wendy G Teeter is the Curator of Archaeology for the Fowler Museum, UCLA NAGPRA Coordinator, and teaches periodically in UCLA American Indian Studies. She is a member of the UC President’s Native American Advisory Council. Teeter collaborates nationally and internationally with Indigenous communities on issues of repatriation and cultural heritage protection. She is Co-PI for Mapping Indigenous Los Angeles, a community-based website devoted to storytelling through cultural geography and map making as well as providing educational resources and curriculum and for Carrying our Ancestors Home, which tells the history of repatriation at UCLA and stories of repatriation from Indigenous communities. Since 2007, Teeter has been co-director of the Pimu Catalina Island Archaeology Project, which seeks to understand the Indigenous history of the island and Tongva homelands through multi-disciplinary and collaborative methodologies. The Project provides a field school that has educated over 150 students on the importance of community-based archaeology. Teeter helped to develop the Tribal Learning Community & Educational Exchange Program in the Native Nations Law & Policy Center, UCLA School of Law in 2003 and serves as on its Advisory Board. In June 2011 she co-curated, “Launching A Dream: Reviving Tongva Maritime Traditions,” at the Fowler Museum at UCLA with Cindi Alvitre (Director, Ti’at Society). She serves on several boards and committees including as Chair of the Society for California Archaeology Curation Committee and Editorial Board Member, Heritage & Society Journal.
Robert (Bob) Wayne - Ecology and Evolutionary Biology, Institute of Environment and Sustainability
Robert (Bob) Wayne, Ph.D.
Distinguished Professor, Ecology and Evolutionary Biology
Distinguished Professor, Institute of the Environment and Sustainability
Wayne Lab’s research projects cover a wide range of species and utilize a multitude of molecular approaches. From exploring contemporary population dynamics to evolutionary relationships, current projects utilize both traditional and next-generation technologies to address ecological and evolutionary questions at a variety of spatial and temporal scales.
Many of the projects explore genomes for signatures of selection (natural or artificial), local adaptation, patterns of partitioning genetic variation across species and populations, or use a metagenomic approach to understand complex biological systems. We also explore the potential of transcriptomics to gather gene expression data from wild populations.
Felipe Zapata - Ecology and Evolutionary Biology
Felipe Zapata, Ph.D.
Assistant Professor, Ecology and Evolutionary Biology
We are broadly interested in organismal biology and the origin and evolution of biodiversity. Our main focus are flowering plants, but we occasionally work with other organisms. We integrate multiple areas of biology, from field to computational biology, to address questions in evolution and systematics.
Victoria Vesna - Design Media Arts, Art|Sci Center
Victoria Vesna, Ph.D.
Artist & Professor, Design Media Arts
Director of the Art|Sci Center at the School of the Arts and California Nanosystems Institute (CNSI)
Although she was trained early on as a painter (Academy of Fine arts, Belgrade, 1984), her curious mind took her on an exploratory path that resulted in work can be defined as experimental creative research residing between disciplines and technologies. With her installations she investigates how communication technologies affect collective behavior and perceptions of identity shift in relation to scientific innovation (PhD, University of Wales, 2000). Her work involves long-term collaborations with composers, nano-scientists, neuroscientists, evolutionary biologists and she brings this experience to students.
Pamela Yeh - Ecology and Evolutionary Biology
Pamela Yeh, Ph.D.
Associate Professor, Ecology and Evolutionary Biology
My lab is interested in measuring, understanding, and predicting the ecological and evolutionary trajectories of populations when they encounter novel environments, particularly environments with multiple disturbances or stressors. We are especially interested in how the stressors interact, and how these interactions ultimately affect populations. We incorporate field, lab, and theoretical tools in our work. We work on two systems, one lab-based, and one field-based. In the lab, we work on microbial evolution and how bacteria respond to multiple stressors, using antibiotics as stressors. In the field, we work on avian urban ecology and evolution, specifically on how dark-eyed juncos and house sparrows are affected by the urban landscape and unique urban stressors.